As a substitute for screen, if you want to be able to run the process in the background without having it shutdown when you exit the server (or drop your connection), then there are few options:
Run the process in a subshell like so:
(myprog -opts &)
Disown the process (if you have bash or zsh) after putting it in the background:
myprog -opts & ; disown
Run the script with nohup:
nohup ./myprog 2>&1 &
In most of the above cases, the process is detached from the user and put under "init". That meant you can safely exit without the process getting shutdown (otherwise, exiting the shell will send a SIGHUP to the program, which will shut it down).
However, you will not be able to reattach to that process. So for whatever program you run using the above options, you'll need to write standard output to file like so (for example, this):
nohup ./myprog 2>&1>myprog.log &
And then monitor that file.